Ubuntu18.04[P9, WSP]: While running ltp kernel_misc test hitting cpu warn_on on unregister_blkdev+0xac/0x300

[bugproxy]

== Comment: #0 - Praveen K. Pandey <email address hidden> - 2018-03-06 05:19:10 ==
Problem Description :

While running ltp kernel_misc test hitting cpu warn_on on unregister_blkdev

Reproducible Step:

1- Install WSP system with Ubuntu18.04
2- get ltp from github

a- git clone https://github.com/linux-test-project/ltp.git
b-cd ltp
c- make autotools
d- ./configure
e- make
f- make install
g- cd /opt/ltp
h- ./runltp -f kernel_misc

LOG:

[87195.381004] WARNING: CPU: 8 PID: 25873 at /build/linux-jWa1Fv/linux-4.15.0/block/genhd.c:400 unregister_blkdev+0xac/0x300
[87195.381166] Modules linked in: ltp_block_dev(OE) sctp nls_iso8859_1 ntfs btrfs zstd_compress xor raid6_pq xfs libcrc32c idt_89hpesx ofpart at24 uio_pdrv_genirq cmdlinepart powernv_flash ibmpowernv vmx_crypto mtd ipmi_powernv ipmi_devintf ipmi_msghandler crct10dif_vpmsum opal_prd uio sch_fq_codel ip_tables x_tables autofs4 ast i2c_algo_bit ttm drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ahci crc32c_vpmsum drm tg3 libahci [last unloaded: ltp_fw_load]
[87195.381750] CPU: 8 PID: 25873 Comm: block_dev Tainted: G OE 4.15.0-10-generic #11-Ubuntu
[87195.381869] NIP: c00000000069808c LR: c00000000069803c CTR: c000000000697fe0
[87195.381967] REGS: c000001cf0bf3970 TRAP: 0700 Tainted: G OE (4.15.0-10-generic)
[87195.382078] MSR: 9000000000029033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 28000822 XER: 20040000
[87195.382177] CFAR: c00000000069805c SOFTE: 1
[87195.382177] GPR00: c00000000069803c c000001cf0bf3bf0 c0000000016ea600 0000000000000000
[87195.382177] GPR04: c008000019e113d8 000000000000000d 00000000636f6c62 c000001cee876a00
[87195.382177] GPR08: c000000001a0f4b8 0000000000000000 0000000000000000 c008000019e111b8
[87195.382177] GPR12: c000000000697fe0 c00000000fa85800 0000000000000000 0000000000000000
[87195.382177] GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
[87195.382177] GPR20: 000007399d9b8c10 000007399d9b8c28 00007fffd61064a4 000007399d9b8c50
[87195.382177] GPR24: 000007399d9b8cf0 000007399d9d0010 c000001cf0bf3e00 00000000000000fc
[87195.382177] GPR28: c008000019e113d8 c0000000015e2a60 0000000000000000 0000000000000000
[87195.383098] NIP [c00000000069808c] unregister_blkdev+0xac/0x300
[87195.383180] LR [c00000000069803c] unregister_blkdev+0x5c/0x300
[87195.383266] Call Trace:
[87195.383302] [c000001cf0bf3bf0] [c00000000069803c] unregister_blkdev+0x5c/0x300 (unreliable)
[87195.383424] [c000001cf0bf3c30] [c008000019e10790] sys_tcase+0x558/0xbe0 [ltp_block_dev]
[87195.383542] [c000001cf0bf3ce0] [c0000000008530dc] dev_attr_store+0x3c/0x60
[87195.383628] [c000001cf0bf3d00] [c00000000049a6b4] sysfs_kf_write+0x64/0x90
[87195.383726] [c000001cf0bf3d20] [c0000000004993ac] kernfs_fop_write+0x1ac/0x270
[87195.383824] [c000001cf0bf3d70] [c0000000003cf8dc] __vfs_write+0x3c/0x70
[87195.383919] [c000001cf0bf3d90] [c0000000003cfb38] vfs_write+0xd8/0x220
[87195.384009] [c000001cf0bf3de0] [c0000000003cfe58] SyS_write+0x68/0x110
[87195.384103] [c000001cf0bf3e30] [c00000000000b184] system_call+0x58/0x6c
[87195.384196] Instruction dump:
[87195.384241] 419e0030 812a0008 7f89f000 409e0018 48000144 813f0008 7f89f040 419e0058
[87195.384347] 7feafb78 ebea0000 2fbf0000 409effe8 <0fe00000> 7fa3eb78 3be00000 48668431
[87195.384459] ---[ end trace fdc18fb4b5cc1498 ]---

Regards
Praveen

[Joseph Salisbury (jsalisbury)]

Did this issue start happening after an update/upgrade? Was there a prior kernel version where you were not having this particular problem?

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v4.16 kernel[0].

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.16-rc4

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2018-03-13 07:27 EDT-------
@praveen: your reply is required for this bug.

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2018-03-15 15:23 EDT-------
@praveen: your attention required on this bug.

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2018-03-25 21:53 EDT-------
(In reply to comment #6)
> Did this issue start happening after an update/upgrade? Was there a prior
> kernel version where you were not having this particular problem?
>
> Would it be possible for you to test the latest upstream kernel? Refer to
> https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v4.16
> kernel[0].
>
> If this bug is fixed in the mainline kernel, please add the following tag
> 'kernel-fixed-upstream'.
>
> If the mainline kernel does not fix this bug, please add the tag:
> 'kernel-bug-exists-upstream'.
>
> Once testing of the upstream kernel is complete, please mark this bug as
> "Confirmed".
>
> Thanks in advance.
>
> [0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.16-rc4

@Praveen: Gentle reminder to get back on above comments.

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2018-03-26 10:19 EDT-------
Hi

Verified this latest ubuntu main line kernel and seems me issue fixed

root@system:/opt/ltp# uname -a
Linux system 4 4.16.0-041600rc7-generic #201803252030 SMP Mon Mar 26 01:43:33 UTC 2018 ppc64le ppc64le ppc64le GNU/Linux
root@system:/opt/ltp# dmesg
[ 910.983501] LTP: starting fw_load
[ 910.984640] LTP: starting rtc01
[ 911.120171] LTP: starting block_dev
[ 911.121381] LTP: starting tpci
[ 911.122599] LTP: starting tbio
[ 911.123804] LTP: starting ltp_acpi
[ 911.125134] LTP: starting cpufreq_boost
[ 911.126466] LTP: starting uaccess
[ 911.127925] LTP: starting rcu_torture (rcu_torture.sh)
[ 911.136024] LTP: starting lock_torture (lock_torture.sh)
[ 911.144424] LTP: starting zram01 (zram01.sh)
[ 911.153661] zram: Added device: zram0
[ 911.154420] zram: Added device: zram1
[ 911.155591] zram: Added device: zram2
[ 911.155819] zram: Added device: zram3
[ 911.164303] LTP: starting zram02 (zram02.sh)
[ 911.177847] zram: Removed device: zram0
[ 911.205133] zram: Removed device: zram1
[ 911.225471] zram: Removed device: zram2
[ 911.249079] zram: Removed device: zram3
[ 911.288132] LTP: starting zram03
[ 911.293990] zram: Added device: zram0
[ 911.296299] zram0: detected capacity change from 0 to 536870912
[ 911.476528] zram: Removed device: zram0
root@system:/opt/ltp#

Regards
Praveen

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2018-04-06 11:18 EDT-------
Hi,

I understand that this bug is still being debugged and we still do not have the fix for this problem, right?

It was just mirrored to Canonical for their awareness, correct?

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2018-04-24 02:40 EDT-------
What is the update on this bug from validation point of view.
Please update this defect by validating with latest kernel version.

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2018-04-24 09:39 EDT-------
(In reply to comment #23)
> What is the update on this bug from validation point of view.
> Please update this defect by validating with latest kernel version.

Kalpana,

The kernel GA has got the error with LTP test(kernel_misc), but the latest version of tag Ubuntu-4.15.0-17.18 worked well.

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2018-04-24 11:15 EDT-------
(In reply to comment #24)
> (In reply to comment #23)
> > What is the update on this bug from validation point of view.
> > Please update this defect by validating with latest kernel version.
>
> Kalpana,
>
> The kernel GA has got the error with LTP test(kernel_misc), but the latest
> version of tag Ubuntu-4.15.0-17.18 worked well.

Ubuntu-4.15.0-17.18 ---> daily build kernel right? Where can we get GA builds?

Praveen: please double confirm from daily build vs. GA build and update the defect.

[Joseph Salisbury (jsalisbury)]

Can you confirm this bug is now resolved in the latest 18.04 kernel?

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2018-04-24 13:34 EDT-------
Hello,

Well, with released kernel 4.15.0-19 via apt-get, the test does not show a call trace again, it's good.

walbon@ltc-wspoon5:/opt/ltp$ uname -a
Linux ltc-wspoon5 4.15.0-19-generic #20-Ubuntu SMP Sun Apr 22 00:02:03 UTC 2018 ppc64le ppc64le ppc64le GNU/Linux

walbon@ltc-wspoon5:/opt/ltp$ sudo ./runltp -f kernel_misc
<<<execution_status>>>
initiation_status="ok"
duration=0 termination_type=exited termination_id=2 corefile=no
cutime=2 cstime=16
<<<test_end>>>
INFO: ltp-pan reported some tests FAIL
LTP Version: 20180118-227-gc57eb29af

###############################################################

Done executing testcases.
LTP Version: 20180118-227-gc57eb29af
###############################################################

walbon@ltc-wspoon5:/opt/ltp$ dmesg
[ 250.864009] LTP: starting fw_load
[ 250.865149] ltp_fw_load: version magic '4.15.0-15-generic SMP mod_unload mprofile-kernel' should be '4.15.0-19-generic SMP mod_unload mprofile-kernel'
[ 250.865529] LTP: starting rtc01
[ 251.009076] LTP: starting block_dev
[ 251.010040] ltp_block_dev: version magic '4.15.0-15-generic SMP mod_unload mprofile-kernel' should be '4.15.0-19-generic SMP mod_unload mprofile-kernel'
[ 251.010409] LTP: starting tpci
[ 251.011058] LTP: starting tbio
[ 251.011732] LTP: starting ltp_acpi
[ 251.012456] LTP: starting cpufreq_boost
[ 251.013190] LTP: starting uaccess
[ 251.014100] ltp_uaccess: version magic '4.15.0-15-generic SMP mod_unload mprofile-kernel' should be '4.15.0-19-generic SMP mod_unload mprofile-kernel'
[ 251.014457] LTP: starting rcu_torture (rcu_torture.sh)
[ 251.018531] LTP: starting lock_torture (lock_torture.sh)
[ 251.022937] LTP: starting zram01 (zram01.sh)
[ 251.032878] LTP: starting zram02 (zram02.sh)
[ 251.040056] zram0: detected capacity change from 536870912 to 0
[ 251.040754] zram: Removed device: zram0
[ 251.077017] zram: Removed device: zram1
[ 251.108949] zram: Removed device: zram2
[ 251.144992] zram: Removed device: zram3
[ 251.192976] LTP: starting zram03
[ 251.196905] zram: Added device: zram0
[ 251.198520] zram0: detected capacity change from 0 to 536870912
[ 251.377049] zram: Removed device: zram0

[Frank Heimes (fheimes)]

Since 18.04 was released with 4.15.0.20:
$ rmadison --arch=ppc64el linux-generic | grep bionic\
 linux-generic | 4.15.0.20.23 | bionic | ppc64el
I'm closing this ticket as Fix Released